June 21, 2010

Brown-eyed men perceived to be more dominant

(Last Update June 21)

The authors discovered that males with brown eyes were considered more dominant than males with blue eyes, but when they altered their pictures to turn brown eyes into blue, the effect persisted. Thus, it is not the color itself that creates the impression of dominance, but rather other factors correlated with the brown-eyed phenotype.

One of these "other factors" could be chin breadth, which is known to be perceived as dominant. From the paper:

The question arises: why are brown-eyed males rated as more dominant than blue-eyed? Some facial features such as square jaws, thick eyebrows and broad cheekbones are linked with higher perceived dominance; facial submissiveness, on the other hand, is characterized by a round face with large eyes, smallish nose, and high eyebrows (Berry, 1990; Berry & Mcarthur, 1986; Cunningham,Barbee, & Pike, 1990; Mazur, Halpern, & Udry, 1994; Mueller & Mazur,1997; Thornhill & Gangestad, 1994). The morphological differences between blue-eyed and brown-eyed males were visualized by deformation of thin-plate splines (Fig. 3). In contrast with blue-eyed males, brown-eyed males have statistically broader and rather massive chins, broader (laterally prolonged) mouths, larger noses, and eyes that are closer together with larger eyebrows. In contrast, blue-eyed males show smaller and sharper chins, mouths that are laterally narrower, noses smaller, and a greater span between the eyes. Especially the broader massive chin, bigger nose, and larger eyebrows of brown-eyed males may explain their higher perceived dominance.

The authors propose that true genetic linkage between eye color and these other facial features is unlikely, as eye color is determined by few loci, and these are unlikely to be the same ones that influence these other facial features. Thus, they propose a different explanation, namely that blue-eyed and brown-eyed children are treated differently by their parents as they grow up, and this "different treatment" manifests itself phenotypically. The argument in favor of different treatment stems from the fact that many people are born blue-eyed, but their eye color is set to a darker shade eventually. The authors write:

It is possible that subjects with blue eyes are treated as a small child for a longer period than brown-eyed children. Such early social experience may have been literally ‘‘inscribed” into their faces, preserved until adulthood, and finally bring on the perception of higher submissiveness. Rosenberg and Kagan (1987, 1989) investigated the association between eye color and behavioral inhibition, revealing that children with blue eyes are more inhibited. Coplan et al. (1998) found a significant interaction between eye color and social wariness within preschoolers. Blueeyed males were rated as more socially wary, i.e. being more temperamentally inhibited, displaying more reticent behavior and having more internalizing problems, than males with brown eyes, though there were no differences between blue- and brown-eyed females (Coplan et al., 1998).

There is an alternative explanation, that requires neither genetic linkage nor an environmental factor such as upbringing. That factor is latent population structure.

In a truly long-term random mating population, and assuming that eye color is not genetically linked with e.g. chin breadth, then all combinations of chin breadth and eye color would occur with a probability determined entirely by the frequency of their genetic determinants in the population.

However, consider the possibility that the population is an incomplete mixture of a blue-eyed "facially submissive" population element, and a brown-eyed "facially dominant" one. If that was the case, then brown-eyed folks would tend to have dominant facial features by reason of their ancestry rather than any genetic linkage between the two traits.

As an analogy, consider a hypothetical population made up of Europeans and East Asians. Initially, there would be a statistical association between straight hair and short stature in the total population that would be entirely due to population structure rather than either pleiotropic effects of genes affecting both characters or genetic linkage of hair/stature genes.

The Czech population is intermediate in its bigonial diameter between Germans and Slovaks (its immediate neighbors) [1], they are also genetically intermediate between Germans and Slavs. Procopius noted in early medieval times that Slavs had intermediate pigmentation. So, I wouldn't discount the possibility that population structure due to incomplete blending may account for eye color/facial structure associations in this population.

UPDATE:

Here are some values for German and Czech males from [1].

Bigonial (go-go): 97.6 / 109.5

Nasal height (n-sn): 52 / 54.0

Nasal breadth (al-al): 34.0 / 36.2

Mouth breadth (ch-ch): 50.9 / 53.8

Intercanthal distance (en-en): 31.2/30.9

Unfortunately there is no data for the eyebrows, but all of the above differences are in the expected direction under my theory: Germans have narrower jaws, smaller noses, narrower mouths, and eyes placed further apart than Czechs.

So, I think it is quite likely that the blue-eyed facially submissive type found in this sample may have a German origin.

PS: I did an average of the blue- and brown-eyed averages for reference:

Eye color predicts but does not directly influence perceived dominance in men

Karel Kleisner et al.

This study focuses on the relationship between eye color, gender, and psychological characteristics perceived from the human face. Photographs of 40 male and 40 female students were rated for perceived dominance and attractiveness. Attractiveness showed no relation with eye color. In contrast, eye color had a significant effect on perceived dominance in males: brown-eyed men were rated as more dominant than men with blue eyes. To control for the effect of eye color, we studied perceived dominance on the same photographs of models after changing the iris color. The eye color had no effect on perceived dominance. This suggests that some other facial features associated with eye color affect the perception of dominance in males. Geometric morphometrics have been applied to reveal features responsible for the differences in facial morphospace of blue-eyed and brown-eyed males.

26 comments:

Procopius noted in early medieval times that Slavs had intermediate pigmentation.

According to the 10th century Persian historian and geographer Ibn al-Faqih, there were two types of Slavs: those with swarthy skin and dark hair that live by the sea and those with fair skin and light hair that live farther inland. The former is probably a reference to southern Slavs, while the latter is probably a reference to northern Slavs (both western and eastern ones), both descriptions are in accordance with the physical characteristics of modern northern and southern Slavs (of course, in a rough way, as Ibn al-Faqih's descriptions are rough generalizations). Southern Slavs (Bulgarians and former Yugoslavian Slavs) are known to be genetically very highly admixed with native Balkan people, so northern Slavs, especially those that live around the Slavic homeland, represent the ancestral Slavic type much better. So it is safe to say that the original Slavs had fair skin, light hair and concomitant light eyes (of course, here I am making a rough generalization like Ibn al-Faqih). Procopius' reference may have been just to southern Slavs (who were much closer to the Byzantine territory than northern Slavs) and their native Balkan subjects and slaves, who were then probably in a process of fusion, and southern Slav aristocrats and soldiers may already have been highly admixed with native Balkan people then.

Procopius lived during the time when the Slavs crossed into the territory of the Roman Empire, so I don't really see any reason why he would confuse the Slavs with the pre-Slavic population of the Balkans that would eventually be Slavicized.

The eastern Slavs themselves acknowledged that they were darker than Balts and Finns. See also this.

I should also note that the apellation "Slav" was given by Arab writers to Germanics:

"So while the Frankish, Slavic (among whom the Germanic peoples were counted) and Turkic (which were thought to include the Russians and the Volga Bulgars) peoples and other inhabitants of the sixth zone were generally melancholic and splenetic folk"

Procopius lived during the time when the Slavs crossed into the territory of the Roman Empire, so I don't really see any reason why he would confuse the Slavs with the pre-Slavic population of the Balkans that would eventually be Slavicized.

OK, you may be right about the confusion issue, but still, the Slavic aristocrats and soldiers he saw may have already been highly admixed with Balkan natives.

The eastern Slavs themselves acknowledged that they were darker than Balts and Finns.

It is very normal Eastern Slavs to be darker than Balts and Finns, because, as you acknowledge, the Baltic area and environs is the center of depigmentation among Caucasoids.

See also this.

As to your Bohemia argument, I don't think Czechs represent the ancestral Slavic type, as the Slavic homeland was more to the northeast, probably somewhere around Belarus, Poland, European Russia and Ukraine.

I should also note that the apellation "Slav" was given by Arab writers to Germanics:

"So while the Frankish, Slavic (among whom the Germanic peoples were counted) and Turkic (which were thought to include the Russians and the Volga Bulgars) peoples and other inhabitants of the sixth zone were generally melancholic and splenetic folk"

Medieval Islamic writers also used the word "Slav" ("Siqlabi" in Arabic) to denote only the Slavic speakers. I don't know which was the meaning used by Ibn al-Faqih, but as he was a scholar and not a politician or military leader, it is very probable that he used the word only to denote Slavic speakers.

That's another case of total idiocy. They just take a small sample and conclude from that things which are totally absurd.

They should have looked for the population structure and typological correlations in the population in the first place. Because if you have a population in which the lighter individuals have significantly more Baltid influences than the darker ones, which have significantly more Dinarid and Mediterranid influences, it's quite obvious how this "result" came along.

It has zero to do with blue eyes and even less to do with uprising - sorry - they seem to be retarded not to look at the older works if doing such a job and coming up with a milieu theory which is just.

It's so obvious they deal with different racial forms in their sample, the pigmentation is just the clue to that, one of the decisive traits, but not the reason in itself.

Would they have done the same in Norway, things might have looked very different actually.

I think that the color of the eyes don't count very much to make an attractive man. It can be a something more, an accessory, but what really counts it is the form of the oval.You can observe Mediterranean men with blue eyes, but with developed chin too and they are considered very attractive, as the actors Alain Delon or Franco Nero. Their blue eyes are almost an element of strangeness but attractive.This because the small chin is considered a female characteristic and a manwith this characteristic can seem a few virile.

Recent genetic studies like Underhill 2009 showed that Slavic R1a1a has been present in Central Europe since the Neolithic. Slavic population there is quite old and homogenous genetically. So probably Proto-Slavs looked more less like people living there now, as they are the same people. Migrations didn’t affect Central and Eastern Europe as much as some people thought.Slavs are not mixed with Balts and Fins, who are predominantly N1c, not present in Poland. Also very little Celtic and Germanic admixture – R1b around 10% in Poland to 2% in Russia. A lot of R1b comes from Armenians, Jews and other minorities. I1 is at negligible level and some clades like I1-P are exclusively Polish not present anywhere else .East Germany on the other hand is heavily mixed with Slavs, around 30% R1a1a and East European modal haplotypes . Slavic language was spoken there till XVIII century. That’s why East Germany has higher percentage of blue eyes than West Germany.Also there are some very useful autosomal studies like Neils 2009 which show that Slavs like Russians and Poles are close together and quite distinct from Balts, Fins, Celts and Germans:http://www.plosone.org/article/fetchObjectAttachment.action;jsessionid=A21D61BCC1F57A07CE0026CA37354422?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0005472&representation=PDFSouthern Slavs are heavily mixed with Balkanic population, so they are naturally darker.Ancient Slavs of Central Europe, Corded Ware and Andronovo R1a1a people were the same people, and they were close to Poles and Russians autosomally and pigmentation wise as some studies show . They also spoke similar languages as Slavic languages are the most conservative and archaic Indo-European languages most similar to Proto-Indo-European and closely related to Indo-Iranian. Linguists like prof. Alinei linked Corded Ware with Proto-Slavic language and this is now confirmed by genetic studies. Celtic and Germanic people are not R1a1a and cannot be linked with Corded Ware or Andronovo.Pigmentation maps, genetic studies and linguistic evidence fit together and they are all useful.

I am skeptical that dominance perceptions of college students in Prague generalize broadly.

College students in Austin, Texas, or Mumbai, India, for example, might have opposite perceptions.

Stereotyping based on appearance is to some extent a read of links between appearance and local social class structure, and while the authors talk about how appearance may influence actual behavioral patterns in people with a given appearance, the study didn't investigate the actual behavior of the models (i.e. the accuracy of the viewers).

Context matters a lot in creating stereotypes and appearance perceptions. For example, in the United States, a cop, either black or white, is statistically more likely to incorrectly shoot an innocent young black man believing him to have committed a crime than he is to incorrectly shoot an innocent young white man. But, in Afghanistan, a young black man is probably less likely to be shot by a fellow U.S. soldier than a young white U.S. soldier -- almost all black men in the theater are follow alliance soldiers.

As to your Bohemia argument, I don't think Czechs represent the ancestral Slavic type, as the Slavic homeland was more to the northeast, probably somewhere around Belarus, Poland, European Russia and Ukraine.

That's not relevant in this case. The point is that there is mixture between Central European Slavs and German. We only care about medieval CE Slavs.

"R1a1a has been present in Central Europe since the Neolithic. Slavic population there is quite old and homogenous genetically. So probably Proto-Slavs looked more less like people living there now, as they are the same people."

Rather not. Because first of all, R1a1a entered the region in pre-Slavic times and being related to the Corded Ware culture groups in Central Europe probably, which were most likely Indoeuropean, but can't be defined as being "Slavic", even if an ancestral Proto-Proto-Slavic group was among them.

Secondly, that there is a relative genetic continuity means sometimes close to zero for a phenotypical continuity. Obviously the population in the East changed, be it due to modification or selection, most likely both, significantly since early medieval times.

All ancient archaeological complexes which could be defined as being Proto-Slavic or Old Slavic were usually predominantely dolichocranic and most of the time also rather leptoprosopic, so if assuming they were light pigmented = Nordoid rather.

If looking at this morph now, thats nothing like that but similar to the Baltid minority element already present then, but dominant now.

As for the comparison as such, the Dinarid-Mediterranid-Alpine complex being most likely pre-Slavic and/or German, depending on the exact place, the Baltid Eastern European and came mostly with the Slavs, Nordid can be either.

Just speaking about the majority, I don't think Germans or Slavs were THAT homogenous...

Slavs, Baltic people, and Finns all arrived from farther south in relatively recent times. They clearly mixed with fairer people to arrive at their current distribution and current color gradient away from the Baltics, and away from the NW in general.

However, I would think that such a gradient already existed before Slavic expansion, but more importantly, that the people in the main river valleys between the southern Ukraine and Ural mountains (the likely homeland of all three populations above) by far never were as dark as the adjacent S/SE Balkan or Anatolian populations. However, their pigmentation may cause them to get much darker more easily with sunlight (than northern phenotypes).

That's not relevant in this case. The point is that there is mixture between Central European Slavs and German. We only care about medieval CE Slavs.

I guess you don't include Poles among CE Slavs, as they are closer to the ancestral Slavic type (fair skin, light hair and eyes, roughly speaking). Also Poles are probably more depigmented (including skin, hair and eyes) than Germans in their averages (at least that is what I have seen in depigmentation maps so far).

Anyway, as Czechs and Slovaks don't represent the ancestral Slavic type (as they are mainly descended from later Slavicized natives), there is no need to further this debate about the physical characteristics of the original Slavs.

Btw, the brown-eyed Czech composite looks very much like a friend of mine, who is a Balkan Turk.

A small addition to the above: my friend was born in and lives in Istanbul, but he is entirely descended from Balkan Turks that emigrated to Turkey during the turbulent years of the early 20th century (like my mother).

I guess you don't include Poles among CE Slavs, as they are closer to the ancestral Slavic type (fair skin, light hair and eyes, roughly speaking). Also Poles are probably more depigmented (including skin, hair and eyes) than Germans in their averages (at least that is what I have seen in depigmentation maps so far).

Poles are irrelevant since it is unlikely that Procopius would be familiar with them or that the Slavs of early medieval Moravia would look like modern-day Poles.

The evidence (literary and pictorial) is pretty clear that the medieval Slavs relevant to our discussion were darker than the medieval Germans.

Even then the sources say that the Slavs from Bohemia and Moravia are among the darkest of them all.

So I'd say it is just the most likely explanation that this is the result of an already ongoing or existent mixture of early Slavs with locals, which date most likely back to the Neolithics even...

Also I'd say it is perfectly possible that the Slavs of that time, even others, were somewhat darker than the Germanics they were used to see, especially if comparing with the Varangians and Medieval Germans of some areas - I'm speaking of the Arab sources primarily now.

But this somewhat darker means just a frequency and that they were as dark as the complex this composite face shows is quite unlikely - in my humble opinion.

Being depigmented doesn't necessarily correlate with hair colour or eyes (but possibly red - not blonde hair). The most depigmented people in Europe are from Britain and Ireland, not central or eastern Europe. Someone who is depigmented will have a pinkish hue to their skin.

Race studies in those years of Germany (Nazi era) were highly politicized. We should start a new wave of race studies, which will be completely objective and independent from politics and will be based on both genetics and anthropometry.

Also I'd say it is perfectly possible that the Slavs of that time, even others, were somewhat darker than the Germanics they were used to see, especially if comparing with the Varangians and Medieval Germans of some areas - I'm speaking of the Arab sources primarily now.

Don't take ancient sources so seriously, especially when the geographically closest Slavs to Arabs were the Balkan Slavs, the darkest of all Slavs (and the genetically most distant ones to the original Slavs). Northern Slavs (all of non-Balkan Slavs) as a whole probably aren't darker than Germans, but maybe even lighter than them (of course, not in any significant degree of difference). As to Scandinavian Germanics, they are lighter than both Germans and northern Slavs.

Don't take ancient sources so seriously, especially when the geographically closest Slavs to Arabs were the Balkan Slavs, the darkest of all Slavs (and the genetically most distant ones to the original Slavs). Northern Slavs (all of non-Balkan Slavs) as a whole probably aren't darker than Germans, but maybe even lighter than them (of course, not in any significant degree of difference). As to Scandinavian Germanics, they are lighter than both Germans and northern Slavs.

These are probably all to do with population structure much before (probably Neolithic and even Palaeolithic) the appearance of the current ethnicities in the relevant regions.

Old Blog Archive

Dienekes' Anthropology blog is dedicated to human population genetics, physical anthropology, archaeology, and history.

You are free to reuse any of the materials of this blog for non-commercial purposes, as long as you attribute them to Dienekes Pontikos and provide a link to either the individual blog entry or to Dienekes Anthropology Blog.

Feel free to send e-mail to Dienekes Pontikos, or follow @dienekesp on Twitter.